UpClient Logs uptime with uptimes.wonko.com.
UpClient sends the time a computer has been running since its last reboot to the Uptimes Project. The server generates individual & aggregate statistics of various operating system & hardware configurations.

EBML, or Extensible Binary Meta-Language, is a simple XML like binary language for describing data in structured style. EBML was originally designed for use in the Matroska project, but the developers saw that EBML was very flexible and extensible.